For the past eight years, thousands of conservative activists have descended on Washington each spring with dreams of putting a Republican in the White House.

They finally have one - only trouble is, they are not sure he's really conservative.

With Donald Trump's presidential victory, the future of the conservative movement has become entwined with an unconventional New York businessman better known for his deal-making than any ideological principles.

It's an uneasy marriage of political convenience at best. Some conservatives worry whether they can trust their new president to follow decades of orthodoxy on issues like international affairs, small government, abortion and opposition to expanded legal protections for LGBT Americans - and what it means for their movement if he doesn't.

"Donald Trump may have come to the Republican Party in an unconventional and circuitous route, but the fact is that we now need him to succeed lest the larger conservative project fails," said evangelical leader Ralph Reed, who mobilised his organisation to campaign for Trump during the campaign. "Our success is inextricably tied to his success."

Trump is to address the Conservative Political Action Conference tomorrow. Yesterday, White House spokeswoman Kellyanne Conway thanked the conservatives for helping elect Trump.

As conservatives met for their first big sessions yesterday at the gathering in the Maryland suburb of Oxon Hill, they heard a stream of familiar conservative rhetoric.

A panel of GOP governors urged Washington Republicans, who control the levers of power for the first time in a decade, to deliver the results that Republican governors have brought to their states.

"The victory is not on November 8. That is an assignment for change and real reform," said Arizona governor Doug Ducey, urging Trump and his allies in Congress to make good on promises to repeal "Obamacare," enact tax reform, and cut the federal budget.

"As governors, as activists, engaged citizens, we need to hold all elected leaders accountable for results in this cycle right now. We may not get this same opportunity again. We can't squander it."

Social conservatives were thrilled by a Wednesday night decision to reverse an Obama-era directive that said transgender students should be allowed to use public school bathrooms and locker rooms matching their chosen gender identity.

Trump has a somewhat tortured history with CPAC, an annual convention that's part ideological pep talk, part political boot camp for activists. Over the past six years, he's been both booed and cheered. He's rejected speaking slots and galvanized attendees with big promises of economic growth and electoral victory.

At times, he has seemed to delight in taunting them.

"I'm a conservative, but don't forget: This is called the Republican Party, not the Conservative Party," he said in a May interview on ABC's 'This Week.'

The tensions between Trump's brand of populist politics and conservative ideology will be on full display at the three-day conference, which features panels like 'Conservatives: Where we come from, where we are and where we are going' and 'The Alt-Right Ain't Right At All'.

Along with Trump come his supporters, including the populists, party newcomers and nationalists that have long existed on the fringes of conservativism and have gotten new voice during the early days of his administration.

Pro-Brexit British politician Nigel Farage will speak a few hours after Trump.

Organizers invited provocateur Milo Yiannopoulos after protesters at the University of California at Berkeley succeeded in stopping his appearance on campus. But the former editor at Breitbart News, the website previously run by Bannon, was disinvited this week after video clips surfaced in which he appeared to defend sexual relationships between men and boys as young as 13.

Trump "is giving rise to a conservative voice that for the first time in a long time unabashedly, unapologetically puts America first," said Republican strategist Hogan Gidley. "That 'America First' moniker can very well shape this country, but also the electorate and the Republican Party and conservative movement for decades."

Trump's early moves - including a flurry of executive orders and his nomination of federal Judge Neil Gorsuch to the Supreme Court - have cheered conservatives. They've also applauded his Cabinet picks, which include some of the most conservative members of Congress.

But key items on the conservative wish list remain shrouded in uncertainty. The effort to repeal Obamacare is not moving as quickly as many hoped, and Republicans also have yet to coalesce around revamping the nation's tax code.

No proposals have surfaced to pursue Trump's campaign promises to build a border wall with Mexico that could cost $15bn or to buttress the nation's infrastructure with a $1trn plan. Conservatives fear that those plans could result in massive amounts of new spending and that Trump's penchant for deal-making could leave them on the wrong side of the transaction.

"There is wariness," said Tim Phillips, president of Americans for Prosperity.

But with a Republican-controlled Congress, others believe there's no way to lose.

"He sits in a room with Mitch McConnell and Paul Ryan. Is there a bad a deal to be made with those three in the room?" asked veteran anti-tax activist Grover Norquist. "A deal between those three will, I think, always make me happy."